The Cell Centered Database (CCDB) was released in 2002 as a web-accessible database for high resolution 2D, 3D and 4D data derived from light and electron microscopic imaging, including correlated light and electron microscopy. The CCDB encompasses and hosts many types of data in the dimensional range lying between gross morphology and macromolecular structure - the so-called "mesoscale". These data and the software infrastructure that hosts and serves them are unique in scope, presenting to the community data sets laden with information which is technically difficult to obtain but very rich in content, making them particularly valuable for developing computational models of structures and physiological processes that occur in cells and tissues. Envisioned as a grid and/or web-based federated database system from the beginning of the project in 1998, the CCDB pioneered the production of a distributed, connectable repository system for managing and sharing data for a growing research community of microscopists. This proposal aims to provide a stable base of support for a growing community of users of the Cell Centered Database, by refining core services and establishing the facilities needed for CCDB data and software to be openly shared, modified, extended, edited and documented by the expanding participant group. The proposed work is organized into three specific aims: Aim 1. Open Source CCDB: The current system infrastructure will be translated from a centrally supported research product with defined community requirements to an industrymodeled open source project tailored for community wide contribution, customization and refinement. Aim 2: CDB Core Services: The principal components (schema, core services) of the CCDB will be packaged for community distribution and refinement via open source distribution model. Documentaiton will be provided along with specifications for expanded "community contribution" to a repository/collection of core CCDB services. Aim 3: CCDB Client Tools: Existing CCDB client tools will be packaged and distributed for use by the end-user community.